1. Field
The invention is in the field of adapter devices for interconnecting tubing of different sizes, but is particularly concerned with such adapter devices as used with medical appliances.
2. State of the Art
In the medical arts, it is common to employ a variety of syringes and tubes to transfer liquids from one container to another or into a catheter which is connected to a patient. It is also common to transfer a gas, such as oxygen, through a tube from a container in which it is stored to a breathing mask, tent structure, or the like.
One particular use for a catheter connected to a patient is as a feeding tube. For this purpose the catheter is typically passed through the nose and esophagus and into the stomach of a patient. Such a catheter is generally provided with an external, end fitting adapted to receive a luer-type connector attached to a tube having its other end connected to a feeding bag containing a liquid to be introduced into the patient's stomach.
In the use of feeding tubes, it is often desirable to be able to aspirate gastric juices from a patient's stomach. This is generally done by connecting a relatively large syringe to the feeding tube and partially withdrawing the plunger so as to form a vacuum. However, the tip of a large syringe will not fit into a connection fitting adapted to accept a luer-type connector.
Thus, in the past, the end fitting of a feeding tube has been adapted to receive a large syringe, and a short adapter tube has been provided for insertion into the end fitting. Such adapter tube accepts in turn the tip of a small syringe or the luer-type connector of a feeding bag. Although this arrangement is workable, it is necessary to remove the adapter tube before a large syringe can be connected to the end fitting of the feeding tube, and it is not uncommon for the adapter tube to be lost or misplaced.
It is also desirable to be able to seal the end fitting when the feeding tube is not in use, so that foreign objects do not enter the feeding tube, and so that stomach contents are prevented from escaping through the tube. In the past, a separate plug was provided, but more recently a plug connected to the feeding tube end fitting by a flexible strap has been effectively employed. However, when using a plug connected to a flexible strap, it is necessary to remove the adapter tube from the end fitting before the plug can be inserted, again providing opportunity to lose or misplace the adapter tube.